Collapse and runout of granular columns in pendular state

摘要: It is well known that even small amounts of liquid can strongly modify the mechanical behavior granular packings in static and dynamic conditions. This experimental work, therefore, focuses on collapse columns wet materials pendular wetting regime. Different from previous studies, where idealized spherical (glass beads) are typically used, here experiments irregular calcium carbonate particles (coarse sand) were carried out compared with glass sphere results. Particles different sizes (in range 0.8-5 mm) mixed water 0% to 4% w/w poured a rectangular box. Flow was then triggered by removing lateral wall The measured runout distances showed marked differences between two types which could not be explained only terms particle shape or capillary forces. Ring shear tests 3D tomographic reconstructions distribution highlighted role additional mechanisms related spreading at surface, inter-particle friction, contact lubrication.